The Candidate's primary interest is in the study of brain mechanisms underling mental states, particularly in relation to changes in memory function that occur during the course of aging. Many mental health disorders of aging are characterized by abnormal memory decline. Thus, the proposed research should have important implications concerning the pathophysiology of clinical disorders of aging. The Candidate's previous training in clinical psychology, event-related potentials (ERP), and neuropsychology led to his current interest in memory changes with aging and methods of evaluating these changes with neuroimaging. Functional neuroimaging techniques, such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI), provide powerful tools with which to examine regional brain activity during cognitive tasks. In addition, new statistical methods have become available, such as linear structural relations modeling (LISREL) which can be used to test models describing the relationship between brain function cognitive performance. The research project designed to complement this training program involves the development and application of functional neuroimaging activation techniques to examine neural systems mediating memory in young and elderly adults. Specifically, the Candidate proposes to study implicit skill learning in young and elderly subjects. Previous cognitive research indicates that explicit memory is consistently impaired with aging, while changes in implicit memory depend on the specific function examined. For instance, studies of implicit memory suggest that skill learning may decline in older adults, while other types of implicit memory, such as repetition priming are preserved. The initial phase of the research project will include paradigm development off-line in both young and old subjects, and subsequent application as an activation technique for PET in young (30-39) and elderly (70-79) adults. Later phases of the research project will involve the evaluation of skill learning in similar subjects with fMRI. In addition some of the subjects will receive both PET and fMRI during this phase of the project in order to provide data for direct comparisons of the two technologies. LISREL analyses will be used to test models of brain function, including changes in function related to aging.